Evaluation of Evacuation Vehicle Perform ance in Dynam ic I ce Conditions Keith Drover Adam Warrillow
Arctic Potential Why be concerned over safety in the Arctic? � Increased interest and activity in arctic regions � Development of evacuation systems for ice-infested waters has lagged in contrast to open water � Focus has been on the adaptation of open water systems � Arctic regions are susceptible to dynamic ice conditions
Scope � Definition of EER (Escape, Evacuation & Rescue) � Arctic EER challenges � Existing Evacuation Vehicle Designs � Novel Concept designs � Selection & Evaluation Criteria
Defining EER
Safety in the Arctic An EER System consists of three levels 1. Escape – Begins with the initial alarm signal. All personnel proceed to muster stations, where they wait for evacuation instructions. Personnel don lifesaving equipment and begin the evacuation. 2 . Evacuation – Evacuating the platform requires a vehicle of som e sort, w ith the exception of jum ping or being lifted from the platform , w hich is capable of transporting evacuee’s a safe distance aw ay from the danger, usually described as a point of safety. 3. Rescue – Rescue takes place at the point of safety where the evacuee’s are removed from all remaining risk or inherent dangers of the emergency situation. 3 1 2
Focused Study - Evacuation There are many aspects to a complete EER strategy that we WILL not address, but need to be recognized in vessel design and evaluation: � Personnel Protective Equipment � Stand-by Helicopter Evacuation Possibilities � Transferability During Rescue Phase � Stand-by Vessel capabilities � Simplicity of Escape Strategy � Psychological Effects on Crew Abilities � Muster Stations � Protection from the Environmental Conditions during escape
Conditions Encountered in Arctic Regions Open W ater Land Fast/ Hard Pack Dynam ic I ce Conditions I ce Conditions Conditions Possible Evacuation Possible Evacuation TEMPSC Vessel Wheeled or Tracked Vehicle Free Fall Arktos Walk onto ice, Arctic Survival Sled
Evacuation Dynam ic I ce Conditions Hazard Zone Hazard Zone
Safety in the Arctic � The hazard zone may restrict stand-by vessels or supply vessels from approaching the platform during an emergency. � Environmental conditions such as ice and wave conditions may create an unfavorable situation where it is impossible for a stand-by vessel or supply vessel to approach the platform. � Supply vessel’s may be required to leave the area on other duties. During this time an emergency situation may arise. Despite the versatility of the stand-by vessel, there still exists a need for an evacuation craft capable of transiting in dynamic ice conditions.
Arctic EER Challenges
Design Considerations Environment Logistics Design Criteria Existing Vessels Applicable Technology
Environment Logistics Environm ent & Logistics
The Environment - Ice Conditions � Ice conditions affect the choice of evacuation system and potential availability of other options (i.e. use of stable ice as a temporary refuge) � Several factors related to the ice affect the reliability and performance of different evacuation systems: Ice concentration Ice thickness Ice Speed Ice/ wave conditions Ice pressure
� Other Constraints to Recognize: � Low air temperatures � Poor visibility � Polar darkness � Snow and blowing snow � Occasional icing � Remoteness of locations
Logistics � Platform type � method of export and supply � Extent of freeboard � Stand-by vessel and marine fleet support (proximity, frequency, number of vessels, etc) � Awareness of developing or changing hazard zone consequences � Possible Accident Scenario’s
Existing Vessels Existing Vessels
Existing Evacuation Available Evacuation Vehicles � Lifeboat � Free-Fall � Inflatable's � Seascape Life boat � Helicopter � ARKTOS
TEMPSC Studies Conducted • Veitch & Simões Ré (2007) • Northumberland Strait • Transport Canada Phase III
SEASCAPE � Developed in Newfoundland for use in ice environments � The arm enables the lowering of the craft to the sea level
ARKTOS ARKTOS � Has been used in applications such as in the Caspian Sea where it is able to be accessed on land and deployed on a land to (ice or open water) transition � Open water performance in severe conditions is poor � Deployment from platform could be difficult
ARKTOS Performance In the Caspian Sea ARKTOS � Greater than 40cm of ice is required to be able to traverse on top of the ice � Brash ice conditions may result in an accumulation of ice in front of the boxy Arktos impeding mobility � Highly complex machine to operate when compared to a TEMPSC vessel � Relies on the connecting arm to function
Existing Evacuation Craft � Do not seem to adequately perform in the conditions that exist for dynamic ice in arctic regions � Experienced master mariners and industry experts are aware of the deficiency of current craft OR OR
Applicable Technology Applicable Technology
Amphibious Vehicles � Archimedes Screw Tractor � Russian Research vehicles � Military craft
Amphibious Vehicles Key advantages � mobility (universality) � Old technology Key disadvantages � Tend to be heavy vehicles � Costly units � Launchability for high freeboard platforms
Icebreaker Technology � Icebreaker hull design Key advantages � proven design � excellent seakeeping ability Key disadvantages � Weight may be too light to break through thicker ice � Requires much larger lifesaving craft, and hence, more robust launching machinery � Larger size means larger capital cost
Dirigibles � Air Balloons Key Advantages � Universal application � Avoidance of ice altogether � SkyCat Key Disadvantages � Maneuvering � Possibly sensitive to weather conditions � Explosion air currents may impede � Super Fan evacuation
Others… . � Hovercrafts � Capsules or � Submersibles bomb shelters � Operates the same in � Over the ice, removing the all environments � Fixed point of safety need to interact with ice floes � Operational � � Substantial survivability time complexity may be an In 2002, DF Dickins issue Associates evaluated would be required. � High capital cost hovercraft for emergency evacuation and rescue in the Sakhalin offshore for ExxonMobil. � Mat integrity may be an issue
Environment Logistics Novel Design Concepts Criteria Existing Vessels Applicable Technology
Design Criteria � Fenders to minimize the effect of impact with structure and ice, or have inherent structural strength. � Adequate function considering sea spray, atmospheric icing, cold temperature and snow. � Ergonomic adequacy (i.e. account for bulky PPE’s) � High survivability time � Good maneuverability � Self-contained air support system & fire support � Self-righting and capable of survival when subjected to pressures of converging ice field. � Well-sheltered � Quick load time and ease of operation
Novel Concepts
Concept Generation
Evaluation Process Environment Logistics Novel Design Concepts Criteria Existing Vessels Applicable Technology
� General perform ance rated on scale of 1 to 1 0 � Launch Adaptability � Protection from Environm ental Conditions ( Survivability) � Carrying Capacity � Fuel Requirem ents � Recovery � Maintenance Requirem ents � Environm ental Effects
Reliability � In general, reliability is the ability of a person or system to perform and maintain its functions in routine circumstances, as well as hostile or unexpected circumstances. � These concepts can be assessed using reliability performance criteria that involved the ability to escape to the launch area, successfully board and launch the evacuation vessel, navigate to a point of safety, and successfully transfer into a standby vessel.
Reliability continued… . � Bercha Group’s Risk and Performance Tool (RPT) � incorporates the simulation of physical events (i.e. time it takes to load into evacuation vessel) with risk analysis (i.e. probability that vessel will launch).
Cost Considerations � Cost may be a ‘show stopper’, as any development has to be economical. � novel designs tend to impose risks that have an impact on the project, stemming from the inherent uncertainty of performance & lack of regulatory approval. These obstacles need to be considered in calculations of risk, cost and project timeline. � In the Arctic, the cost range may be higher than in open water environments. Capital costs Maintenance costs, injury costs, loss of life Global etc… Glo - ISO bal Standards - Operator Operato ISO -Corporate Standards Stan r dard - Corporate s ARCTIC EER ARCTIC EER Standards
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